Exhaust eduction attachment and muffler for internal-combustion engines



Dec. 1924- 1,521,400

- H. SHAW EXHAUST EDUCTION ATTACHMENT AND MUFFLER FOR INTERNAL COMBUSTION ENGINE$ Filed Aug. 22, 3

Patented Dec. 30, 1924.

UNITED STATES PATENT OFFICE.

Ann names For. m'rnnnnrcounus'nox memes;

Application filed August as, me. Serlal no. 858,878.

To all whom it may concern:

Be it :known that I, .H'ENRY SHAW, sub-. ject of the King of Great Britain, residing at Lyrad, Concord Road, Homebush, New

South Wales, Australia, have invented certain new and useful Improvements in Exhaust Eduction Attachments and Mufilers for Internal-Combustion Engines, of which the following is a specification.

This invention relates to an attachment 7 for exhaust pipes of internal combustion engines, which has been'designed with the obect of improving evacuation of exhaust gases and silencing the noise ordinarily incidental' to their evacuation; thereb to'augment the efiicienc of engines to which it is fitted, and to ren er the riding of cycles and cars .on which it is fitted less irksome by reason of the substantial absence of exhaust noise.

The, silencing device in which the. invention consists is an'improvement in mufiiers of the type in which the stream of exhaust gases is divided and the two streams are caused to collide within a vessel in which expansion takes place, and from which the expanded gases are evacuated through a tail pipe.

I In the accompanying drawings:

.Fig. 1 is a longitudinal section through my mufiler;

Fig. 2 is, a transverse section taken on the line 2-2 Fig. 1;

Fig. 3 is a transverse section taken on the line 33 Fig. 1;,

Fig. 4 is a side elevational view of my mufiler adaptedto set transversely of the exhaust line; and

Fig. 5 is a corresponding end elevation. Referring to Figs. 1 t03, is a tubular throat piece the stem end 11 of which is ada ted to be connected to an exhaust pipe lea ing from the exhaust valve casing of an engine. This throat piece forms the junction of two re-entrantly curved pi es 12 and 13, the open mouths 14-15 of sai pipes being disposed. oppositely with a clearance space 16 diameters of those pipes. The throat piece 50 10 is by preference structurally integral with the cylindrical body or .barrel 9 of the mufiler. To simplify construction and to ofier facility'for openin the mufller for cleaning purposes the bee end cover 17 of etween them about equal to twothe 'mufller is made as a separate member which is spigotted at 18 into the open end of the body 9 and securedby screwed pins or bolts 19. The end cover 17 carries the eduction vent pipe 2O. Said pipe 20 is closed at its forward end 21 within the mufiler body and it is slotted (22) lengthwise at opposite sides-of it. One. lip ,23 of each slot 22 may be inset angularly with the object of imparting whirling motion to ases passing into the pipe from the mufller iody.

The open rear end of the vent pipe '20 may be flared as shown at 24 to disperse the outflowing gases-and reduce their velocity.

A structural adaptation of the mufller for cases in which it is required to dispose it transversely of the direction of the exhaust line from the engine is shown in Figs. 4 and 5. The mufiler body 30 is a .cylindricalstructure closed at the ends 31 and 32 and fitted with a transverse diaphragm 33'which divides it into two chambers 34' and 35. -Apipe 36 is axially disposed in the primary chamber 34, extending from the closed end 31 of said chamber through an. aperture in the diaphragm 33. This pipe is slotted (37) along either side, and one lip 38 of each slot is inset similarly to and with the like object as the insets 23, Fig. 3. The throat piece 48 is split to form two half pipes 40' which embrace the body 30 near the end 31 and the body sides are apertured to rovide passageways from the half pipes 40 into the chamber 34. 41 is the exhaust vent pipe which passes out of one side of the chamber 35, usually parallel with the throat piece..'

48 into whichthe end of the engine exhaust pipe is connected.

The exhausting gas which passes into the throat 11 from the engine exhaust peis split into two streams which rush the opposed vents 14 and 15 and come i'nto collision in the, clearance space 16 and disperse in the mufller body, the as temperature and its volume falling. 1518 dispersed gas still under more or less plenum rushes into the vent pipe 20 through the oppositely disposed lateral slots 22 in it, the two streams again colliding and then dispersing in said pipe and finally assing outof its back and to atmosphere. en the slot lips are inset angularly the gas in the vent pipe 20 has whlrling motion imparted to it, whereby its dispersion is promoted.

In the caseof the transverse body arrangement (Figs. v4 and 5) the operation is substantially the same.

By means of these mufilers the noise of the exhaust is eflectively silenced without causing back pressure such as is incident-to the passing of the exhaust through throttling mufllers, the silencin effect being such that all explosive force is 0st and a coughing exhaust noise only results even when the engine in which the applaratus is filled is operated under load at igh speed.

What I claim as my invention and desire to secure by Letters atent is An exhaustmuflier comprising a forked lgees inflow pipe ha. its forked ends innt with their mh u ifis disposed opposite each other, a wide clearance space being provided between said mouths, an expansion chamber having the ends of said forked pipes entering one end-of it, and an, outla pipe projecting into the other end of said chamber, said outlet ipe being closed at its inner end and slotted along each side of it within said chamber, with one lip of each side slot inbent and adapted to procure a whirling motion in the gases in said pipe.

In testimony whereo I afiix my 818118? ture. HENRY SHAW. 

